Key thing to remember is do not enter CAS without permission. On that basis if you do need to change frequency then do so and notify the new controller that you have not notifed the previous controller and the reason why.
In UCAS you don't actually need to speak to anyone, although I always recommend it. So if you are in UCAS and speaking to say scottish information and the mayday is declared along with radio silence, I would recommend calling either one of the LARS units in the area or a local to the area aerodrome and pass the standard who, what, when and where message and notify the new controller that you have not notifed the previous controller and the reason why.
Last edited by gcolyer; 14th Jun 2007 at 14:05.